Portable seat cushion



FIG. 1 is a top right perspective view of a portable seat cushion showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a rear elevation view thereof;

FIG. 5 is a front elevation view thereof; and,

FIG. 6 is a right side elevation view thereof being a mirror image of the left side elevation view thereof. 

The ornamental design for a portable seat cushion, as shown and described. 